"Acquiesced" was used to inform that Nada-cha had to accept something that he no longer wanted that was necessary.
Explanation:
Naba-cha never invaded the West because he knew and accepted, even reluctantly, that there was a man more powerful than himself and that he would not allow him to conquer the territory. Although he did not like this, he did not protest against the existence of this man and preferred to conquer territories where he would not be a problem. In this sense, the word "Acquiesced" was used, thus promoting the meaning of submission to something, without emitting resistance.
He's hoping to convey the similarities and differences of the German government from governments of the past since that is the purpose of making comparisons.
